STATEN ISLAND, N.Y. -- Firefighters came to the rescue of two police officers outnumbered in Mariners Harbor today, in a scene so chaotic that New York’s Bravest employed a truck-mounted deluge gun -- a water cannon -- to fend off the marauding group of teens.

The scene unfolded at about 3:30 p.m. in front of 83 Harbor Rd., where a large group of teenagers had amassed to confront a teenage girl who lives in the residence.

By the time it was over, two officers were sent to Richmond University Medical Center, West Brighton, for treatment, and nine teens ended up under arrest, said Inspector John Denesopolis, the 120th Precinct's commanding officer. Police also recovered a starter pistol, he said.

The officers were OK, but "banged up," Denesopolis said.

"It was chaos," said one neighbor, who lives across the street but declined to give his name, stating that he feared retaliation. "The yelling got louder and louder and louder... There was probably 50 to 55 kids out here, and they were challenging one girl."

The group was threatening the girl, yelling at her to come out and fight, witnesses told the Advance. That sparked calls to 911, and two officers, one male, the other female, arrived at the scene.

The male officer attempted to arrest a member of the crowd, and the teens turned on him, knocking him to the ground.

"The kids were on top of the cop while the cop was arresting the first person," the neighbor said.

When his female partner tried to intervene, witnesses said, she was knocked down as well. As she was being attacked, she shouted for assistance on her police radio.

"Both police officers were on the ground," said another neighbor, who also requested anonymity. "The kids were attacking them."

The scene happened just a few houses down from the FDNY's Mariners Harbor-based Engine Co. 158. The truck got to the street within moments, witnesses said, and blasted the teens with the engine's cannon-shaped deluge gun to disperse the crowd, according to witnesses. A large police presence, including an NYPD helicopter, soon followed, chasing the teens down to make several arrests.

Denesopolis praised the quick response of the firefighters, saying that he thanked the firehouse brass personally.

"They were very helpful," he said. "They were the closest emergency unit on the scene."

The crowd went to the girl's house because her mother had kept her home from Port Richmond High School for the past five days because of a bullying situation, according to Denesopolis.

"It escalated today when they came to her," he said.

The girl, who identified herself as a sophomore at the school, said the incident escalated from a "he-said, she-said" over picking sides in a gang dispute at school.

"They were waiting for me since Thursday. They wanted to get me for a he-said, she-said. They kept on calling," she said, and when the group arrived at her doorstep, they were carrying "guns, blades and knives."

The girl has a heart condition, relatives said, and at one point, one of the teens taunted her by saying, "We're gonna punch you in the chest. We're gonna fix your heart condition."

As of this afternoon, police had not released the names of the nine arrested, though they'll likely face weapon and felony assault charges, police said.